Packaging with internal pile surfaces

ABSTRACT

Laminar packaging having internal pile surfaces wherein the layers are heat bonded by means of the thermoplastic pile.

United States Patent 1191 Barling et al. 1 Sept. 16, 1975 PACKAGING WITHINTERNAL FILE [Si] Int. CI.*.... 003D 27/00; DO4H 1 H00 SURFACES [58]Field ol Search 161/53. 62. 64. 65, 66 [75] inventors: Eric DouglasBurllng, Chcadlc M6; 20-6/62 62 46 R; 56,306

Hulmc; Mar am Llllan Steel. Runcnrnr boih of England Rdmm Cmd 7 A I k Hd UNITED STATES PATENTS l l 'r f' g? a :mmau mum)Slruiliwrn...........mum... mm i 3.422.952 mm George mm 22 mm; Ju|y n1974 3.696J83 l0ll972 Steel 2 [2 H APPL Primary Examiner-Marion E.McCamish Rem! Amflkaflon Dau Attorney, Agent, or Firm cushman. Darby &[o3] Comlnuation of Sch No. 259.609, June 5. m2. Cushma b do [57ABSTRACT 3 r m m u p i Laminar packaging having internal pile surfacesJune 9' 97' Unhcd Kingdom n; [9670," wherein the layers are heat bondedby means of the Dec. a. 197i United Kingdom sows/7| thc'mp'mic 3 Claims,12 Drawing Figures [52] US Cl. 428/86: 428/88; 428/92;

PATENTEDSEP 1 61976 SHKEIIUEZ FIG.5

FIG.6

PACKAGING WITH INTERNAL FILE SURFACES This is a continuation ofapplication Ser. No. 259.609. now abandoned.

This invention relates to packaging.

Our co-pending British Pat. applications Nos. 53265/69. 27068/70.55241/70. 55242/70. 55243/70. 61324/70. 61325/70. 61326/70. l2336/7l.and 28206/71 describe methods for production of pilesurfaced sheetmaterials.

The pile surfaced sheet material employed according to the presentinvention comprises a foundation sheet which may be semi-rigid or rigid.but preferably is flexible. said sheet being continuous. porous orperforated and having on at least one of its surfaces a pile comprisinga plurality of fibres or fibrils of synthetic polymeric material.preferably of average length of the order of l to 20 mm.

We have found that many of the pile-surfaced products of theaforementioned processes. particularly the products having a close (i.e.dense) pile of fibre lengths averaging greater than about 5 mm and moreparticularly greater than about l mm. and similar pile surfacedmaterials produced by other processes. are useful as mechanicalshock-absorbing or thermal insulating materials. and to this end theymay be fabricated into packaging devices including. for example, bags.envelopes. canons. separatos and the like having mechanicalshock-absorbing or heat insulating properties.

Accordingly. the present invention provides packaging capable ofaffording mechanical and/or thermal insulation which comprises pilesurfaced sheet material having a foundation sheet at least one of thesurfaces of which carries a pile having a plurality of fibres or iibrilsof synthetic polymeric material.

in one method of fabricating packaging having a laminate structure. twopieces of pile-surfaced sheet material may be placed together. or asingle piece folded over. so that two piled regions are in contact. andsome or all the edges sealed together to give a sheet product having adouble thickness of pile sandwiched between two outer sheets. Suchlaminated products have better cushioning and insulating properties thanthe single pile-surfaced material. and do not expose a pile surfacewhich could easily become soiled or damp. They may be fabricated intobags. envelopes. carton liners or the like by techniques well known inthe art; for exam le pieces of the material may be cut and folded (withor without sealing along the edges). and they ntay ilL l5 joinedtogether by adhesives. adhesive tapes. staples.

in one embodiment the packaging takes the form of a bag comprising thepile surfaced sheet materials described above.

Preferably the pile surfaced sheet material forms part ofa "laminate"construction. This may be obtained for example by the application to thepile surface of a second sheet of appropriate material; this secondsheet may itself have a pile surface. the pile being disposed towards oraway from the pile of the first sheet.

This second sheet may be bonded to the pile-surfaced sheet for exampleby means of a suitable adhesive. or (where they are thermoplastic) bysoftening the pile fibrils by the action of heat or solvent and causingthe softened fibrils to adhere to the second sheet; altematively or inaddition the second sheet itself may be rendered adhesive to the pilesurfaced sheet. for example by melting if it is thermoplastic. It is notessential that the second sheet be bonded to the pile-surfaced sheetover a large area; thus it may be preferable for the second sheet to bebonded to the pile-surfaced product only at intervals. for example atdiscrete spots or along lines. e.g. along the edges of the sheets. Wherethe pile is of a thermoplastic material.and bonding is by local heatwelding in which the polymeric material forming the pile is melted andpressed against the second sheet to which it bonds. such bonding willresult in collapse of the pile locally. that it where softening of thepile with consequent adhesion occurs. but such collapse will belocalised so that general collapse of the pile does not occur. Thelaminated structure so obtained comprises two substantially continuoussheets or laminae bonding an lnterlayer comprising a plurality offibrils adhering to at least one of the said continuous sheets.

etc. In addition. if the outer sheets are of heat-scalable plasticsmaterial. pieces may be joined by heat sealing outer sheet to outersheet. Alternatively. use may be made of the heat-sealing properties ofthe polymeric material forming the pile as hereinafter described.

Methods of making pile-surfaced sheet materials suitable for use aspackaging in accordance with the present invention have been mentionedabove. e.g. those described in our earlier co-pending applications.Particularly preferred are the methods which comprise the steps ofinterposing a softened or heat-softenabic fila ment-forming materialbetween a foundation sheet and a heated surface. holding the sheetagainst the softened polymeric material and the heated surface(optionally by pressure from a resilient surface) whereby bonding of thepolymeric material to the sheet and adhesion of the polymeric materialto the heated surface occurs. parting the sheet and the polymericmaterial from the heated surface to form fibrils. filaments or tufts.cool ing the surface of the sheet distant from (i.e. the side away from)the heated surface and disjoining the librils. filaments or tufts soformed from the heated surface.

Prefcrred fibril-forming polymeric materials which may be employed inthe production of a pile-surfaced product for use according to thepresent invention include addition polymers. for example. polymers andcopolymers of ethylene. propylene. butadiene. vinyl chloride. vinylacetate. vinylidene chloride. acrylonitrile and styrene and condensationpolymers. for example polyamldes and polyesters. e.g. of glycols and arrmatic dlcarboxyllc acids. Blends of filament-forming polymeric materialsmay also be used.

As examples of specific thermoplastic polymeric materials that may beemployed we may mention polyethylene. polypropylene. nylon. polyethyleneterephtltalate and polyvinyl chloride.

For reasons of cost. the particularly preferred polymeric material islow-density polyethylene. or blends of low-density polyethylene withbituminous material or with thermoplastlcs scraps.

Our co-pcnding British Pat. applications Nos. l2336/7l and 28206171.describe the preparation of pile-surfaced products having a pile ofthermosetting polymeric material; the pile-surfaced sheet materials oithose applications may be employed as packaging materials as hereindescribed.

The pile is preferably dense (that is. has a large number of fibres orfibrils per unit area). strong and resilient. although the actualdensity. strength and resilience of the pile will be selected in thelight of the in tended use of the packaging. Production of a wide rangeof piles having suitable properties can be effected using the previouslydescribed processes with selection of appropriate materials.

The foundation sheet may be of any suitable matcrial. it may be of anatural or synthetic material. As an example of a natural material wemay mention regnerated cellulose (e.g. Cellophanc). Synthetic materialsfrom which the sheet may be made include for example those describedabove as'being suitable for use as polymeric materials for theproduction of a pile.

Other materials from which the sheet may be made include mctttl. forexample aluminum. mesh or foils. woven or non-woven textiles andlaminates of two or more layers. Preferably. however. the foundationsheet is of paper. which may be newsprint. light. or heavyduty wrappingpaper. kraft paper. or flexible cardboard. There should preferably begood bonding between the polymeric material and the sheet. and highlysized glossy papers may not be suitable as sheet materiais because ofdifiiculty of bonding the highly glazed surface on the polymericmaterial. Papers which are glossy on one side only may be suitableprovided that the polymeric material is applied to the non-glossy side.Laminated or coated papers may be used. and in particular a paper coatedon one side or both sides with a suitable polymeric material may heused. which may eliminate the need for u separatesupply of polymericmaterial in the pile forming process. The use of a paper having apolymeric coating on the side away from the pile may be advantageousalso in that it may impart water resistance to the packaging. or it mayhave desirable aesthetic or other properties. In general. of course. thematerial employed in making up the packaging will be selected in thelight of its intended use. Thus for packaging and carrying heavy items aflimsy material would not be used.

Particularly suitable for certain applications may be packagingcomprising shcct materials consisting of a pile surface attached to afoam. conveniently a polyurethane foam. (which may be rigid butpreferably is flexiblcl foundation layer. of the order of l to ltlmm orllittlt. thick.

One embodiment of the invention is illustrated in FIGS. 2 to 6. l2 andI3 of the attached drawings which relate particularly to bag orenvelope-like containers but illustrate the principle of the inventiongenerally. FIG. 7 shows the use of pile-surfaced material as insulantforpipes. and in FIGS. 8-" the pile-surfaced matcriul is employed as bottleseparating partitions. All such applications are contemplated andcovered herein by the term packaging".

FIG. I shows in perspective a portion of pile-surfaced materialcomprising a foundation sheet I and pile 2.

FIG. 2 shows in plan a flat blank cut to shape from a piece of materialas shown in FIG. I. AA is a fold line about which the blank may befolded to the shape shown in FIG. 3 (a section along the line BB isshown in FIG. 4). which may then be folded along line CC. When the pileis of thermoplastic material it may conveniently he beat welded toeffect adhesion of the sides of the material to a bag form as shown inFIG. 5. Thus. in FIGS. 3 and 4 regions 2 are exposed pile surfaces. andregion 3 is a weld line where the pile has collapsed. Similarly regions4 are weld lines in FIG. 5.

It will be appreciated that the product shown in FiO. .i need notundergo further folding. but may provide a simple pile lined bag merelyby sealing of a third side.

in which case. of course. one or both of the extended pile surfacedregions 2 may not be necessary.

A bag shaped container obtained as illustrated in FIGS. 2-5 may findapplication as a heat-insulating container. for example for frozen food.ice cream etc. or. for hot foods. as. for example take-out" conveniencefoods. They may also find application as padded containers. e.g.envelopes. for the packaging and transportation of books and the like.and also. where the pile is of an appropriate thickness and resilience.of more fragile articles for example glass bottles. sample tubes.watches and electronic and engineering equipment. Envelopes may beprovided with a flap and a closure means of an appropriate kind forexample as illustrated in FIG. 6. thereby giving padded closableenvelopes.

in another embodiment a bag or envelope has walls which comprise alaminate construction in which the walls have an inner and outer sheetcomponent between which extends a pile; the inner sheet. or liner. is ofthermoplastic material. and the components of the laminate are bondedtogether by heat welding whereby by melting of the thermoplastic sheet.and/or the pile if it also is thermoplastic. the sheets are joinedtogether. The materials employed must of course. be compatible. i.c.they should be capable of being heat welded togcthcr.

One method of making a bag having such a thermoplastic lining componentis as follows:

A four layer sandwich was formed comprising two rectangular pieces of0.075 mm thick. low density polyethylene sheet interposed between twosimilarly sized rectangular pieces of a pile surfaced sheet material.the pile on which extends towards the polyethylene sheet. The pilesurfaced sheet material was stout krafl papcr having. as a coating onone of its surfaces. a multiplicity of fibrils of low densitypolyethylene. the fibrils having ttn average length in the range 3-6 mm.A continuous weld was formed around three edges of the sandwich byheating and pressure. so that the pile melted and bonded to thepolyethylene liner. leaving a fourth edge open to allow introduction ofan article between the polymeric sheets. Welding. may of course followintroduction of the article between the sheets and the weld pattern maybe such that the article is retained thereby between the sheets.

Thus. for example. in an alternative method. a four layer sandwich isformed as above. an article inserted between the polymeric sheets andthe four layers welded together in a localised area extending along thewhole of the perimeter of the sandwich. in this way the article isencapsulated by an airand water-tight envelope.

in a further method. each of the walls of the bag is produced separatelyby welding a polymeric sheet and a pile-surfaced sheet material togetherin localised areas. Two such walls arranged in superimposed rciation- 5by a tube formed from 1 laminated sheet obtained as described above.

The material. in either the pile-surfaced form or preferably indouble-layer enclosed pile" form. may be fabricated into dividers foruse as partitioning in crates or cartons intended to hold a number ofbottles. glasses or other fragile articles. Bottle dividers are normallymade by assembling a number of pieces of cardboard or other stiffmaterial of the shape shown in FIG. 8. and engaging the slots togetherso as to build up a structure tat shown in FIG. 9. Bottle dividers maybe formed from pile-surfaced material stuck together foundation surfaceto foundation surface. giving a construction shown in plan view in FIG.10. Alternatively. material with an inner pile layer and two outercontinuous sheets may be employed; preferably the edges of the laminatewill be heat-sealed. The construction is shown in plan view in FIG. llwith the heat-sealed edges marked 5.

Further examples. describing also preparation of the pile surfacedmaterial. are as follows:

A sheet of brown wrapping paper. 90 gm". was fed into a Kodak IS TCglazing machine with a hot roll at l50C and a layer of polyethylene film(two piles each $\lrm thick) was fed at the same rate between the paperand the hot roll. The contact time of the paper and film on the hot rollwas approximately 30 seconds and during this time the paper and filmwere held in contact with the hot roll by pressure applied to an endlessbelt of resilient material. The paper sheet was parted from the hot rolland a blast of air directed at the side of the sheet nearest to the hotroll. The product was a sheet of paperhaving firmly bonded to it a softpile of polyethylene fibrils approximately mm long.

A sheet of the material was fabricated into a bag by the methoddescribed and illustrated in FIGS. 2-5.

A quilted product having the aforementioned laminated structure wasobtained as follows:

A sheet of woven nylon textile matei'ial having a'piie of low densitypolyethylene fibres of average length about 1.5 cm was folded so thatthe fibres were sand- (til wiched between the nylon sheet. the edgeswere heat sealed to produce a sandwich comprising two outer sheets ofnylon material with an inter-layer of polyethylcne pile.

Welding of the polyethylene pile inter-layer along intersccting linesproduced a product having a typical quilted appearance. This welding waseffected by pressing the laminate between platens heated to atemperature of about C. The platens had a pattern of matching ridges onboth surfaces. whereby linewise welding together of the nylon sheetsoccurred by melting of the polyethylene.

The quilted product could be employed for furniture covering. garments.bed covers. in addition to their use as packaging or protectivematerials.

in a further embodiment an insulating bag was made having walls eachconsisting of a laminate comprising two outer sheets of HD polyethyleneseparated by an inter-layer of pile. the bag being formed by folding thelaminate as described with reference to FIG. 3. In an alternativeembodiment the laminate was formed into a tube. sealed with onelongitudinal seal. Bag tlcCiitms of appropriate lengthwere then cut offfrom the length of tube so formed. and the tube flattened and sealed toclose off the bottom.

What we claim is:

I. Laminar packaging comprising a first layer consist ing of abackingmaterial heat bonded to a pile of thermoplastic material by meansof said thermoplastic iaminated to a second layer also consisting ofbacking material heat bonded to a pille of thermoplastic.material bmeans of said thermoplastic said layers being bonded with the pilesurfaces adjacent each other.

2. Laminar packaging according to claim I in which said first and secondlayers are laminated over only certain selected areas.

3. Laminar packaging according to claim I in which the first and secondlayers are laminated by heat bonding of the thermoplastic rmaterial.

i Q i i Q

1. LAMINAR PACKAGING COMPRISING A FIRST LAYER CONSISTING OF A BACKINGMATERIAL HEAT BONDED TO A PILE FO THERMOPLASTIC MATERIAL BY MEANS OFSAID THERMOPLATIC LAMINATED TO A SECOND LAYER ALSO CONSISTING OF BACKINGMATERIAL HEAT BONDED TO A PILE OF THERMOPLASTIC MATERIAL BY MEANS OFSAID THERMOPLASTIC SAID LAYERS BEING BONDED WITH THE PILE SURFACESADJACENT EACH OTHER.
 2. Laminar packaging according to claim 1 in whichsaid first and second layers are laminated over only certain selectedareas.
 3. Laminar packaging according to claim 1 in which the first andsecond layers are laminated by heat bonding of the thermoplasticmaterial.